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Hi Guys,

I'm a newb here and pretty new to cars so very much getting my head around stuff. I drove a member of SAU's R33 series 1 and liked it, decide i want a skyline to have some fun it before i settle down. I have an R33 series 2 coming from japan in the near future (won at auction over the weekend) and am trying to learn as much as possible before then and get a little decisive about my options and what i need.

Rims and tyres. Ok this is my situation, i live on an acreage, far from smooth roads i'll tell you that. So i dont want a stiff and bumpy ride. What things have the biggest impact on ride stiffness and smoothness? Is it suspension, tyres, rim size and thus tyre profile?

Originally i wanted 18" rims, but then i heard if i got that i'd need to lower it otherwise it would look ridiculously high. And i can't really afford to do that.... or is the stock suspension just crap?

I was also told 17" would provide a much smoother ride due to more rubber on the tyres, and would provide better performance aswell.

SO....Whats the go fella's? I really am at a loss and need the collective expertise of SAU to guide me in my decision making process.

Rim size has the biggest impact.

19" - hope you drive on smooth roads

18" - bearable but looks the best

17" - best compromise between comfort, looks and performance

16" - too much sidewall in tyres - not as good in performance.

If you have 18" you won't necessarily need to lower it - remember that when changing rims the diameter of the wheel/tyre should stay the same as the stock rim/tyres so that your speedometer will not be rendered inaccurate.

You want to keep the same diameter as stock rim + stock tyre.

So if you get a bigger rim, it means the tyre size (profile) has to be smaller - low profile tyres.

See this thread:

http://www.skylinesaustralia.com/forums/in...showtopic=84208

for information on what rims and tyres people have used successfully.

basically you will need 35 profile tyres if you get 18" rims to keep it the same rolling diametre as stock

so personally i'd go with a 245-265 width tyre, 35profile to keep speedometre correct and 18" because they are large enough to look good.. and not get stupid with tyre prices, (allthough still expensive, dont get me wrong).. but also guard bashing or lip rolling... my mate had 19"s on his 33.. and he had trouble turning!

basically you will need 35 profile tyres if you get 18" rims to keep it the same rolling diametre as stock

so personally i'd go with a 245-265 width tyre, 35profile to keep speedometre correct and 18" because they are large enough to look good.. and not get stupid with tyre prices, (allthough still expensive, dont get me wrong).. but also guard bashing or lip rolling... my mate had 19"s on his 33.. and he had trouble turning!

That's not necessarily correct... the profile is a percentage of the tyre width, so if you went for a 265 on the rear, you'd be right and want a 35 profile (to keep rolling diameter similar to std)... However a 265 won't fit on the front of a R33 gtst, so you'd need a 235 width tyre with a 40 profile for the front... they're the most common 18" tyre sizes for a 33gtst.

Something to consider also is the relative higher expense of an 18" tyre over a 17".... in your case I would stick with a 17 for overall looks and maintaining some sidewall height for compliance.

cheers

Also, with a 18S/35 lower profile tyre combo your more likely to scratach the crap out of your rims ad there is less space between them and the road. 17s with your stock suspension should do good on tyhe bumpy roads. Coilovers would just be plain annoying.

What things have the biggest impact on ride stiffness and smoothness? Is it suspension, tyres, rim size and thus tyre profile?

And the answer is.....

SUSPENSION. The car you are bringing in from Japan probably has Japanese after-market suspension - designed for super-smooth Japanese highways. Rip them out and fit a compliant suspension set, one that won't end up rattling the fillings out of your teeth.

The profile of the tyre will provide some softness to the overall ride quality, but nothing in comparison to the spring/shocker combo fitted to the car.

For wheels, stick to 17" rims. 18s might "look awesome", but they are heavier, and contribute to an increase in unsprung weight of the car; that, in turn, detracts from the handling performance.

17" tyres provide the best combination of performance available for $$ spent. Generally, 235/45x17 tyres are the most affordable of the low-profile performance tyres around, and will fit the majority of aftermarket rims that might be suitable for your car.

Thank you very much blind elk. I am 90% sure the car has stock suspension, not aftermarket. I have concluded 17" is also for me. Money is a factor, but its not incredibly tight. I do want to put some decent rubber on whatever rims i get. And was thinking a wider tyre on the rear for performance, but just not sure what to go with? ie front and rear combo?

For wheels, stick to 17" rims. 18s might "look awesome", but they are heavier, and contribute to an increase in unsprung weight of the car; that, in turn, detracts from the handling performance.

GTR34 18x9s are 9.4kg :rolleyes:

sorry, couldn't help it ;)

hey guys, just thinkin about this the other day, when i had my 16" on the r33 it look alot lower than it is now with my 18's on? does this make sense??

Any pics to show?

Hey guys so i dont think i have gotten a solution to my original post. I know i am going to get 17" rims, and pretty much set on the falken 451 tyres... but what size tyre combo for front and back?? Good handling and grip in the dry, but at the same time not too dangerous in the wet. Thoughts?

don't go narrower than 225. i think having the same width all round is better as the car has an even amount of grip available at each axle. eg if you have narrower tyres on the front, car will be more biased towards understeer (will require less steering effort though).

Hey guys so i dont think i have gotten a solution to my original post. I know i am going to get 17" rims, and pretty much set on the falken 451 tyres... but what size tyre combo for front and back?? Good handling and grip in the dry, but at the same time not too dangerous in the wet. Thoughts?

Depends on what width rims you get. If you are planning on getting a staggered set ie 17x8 fronts, 17x9 rears then 235s on the front and 265 on the rears. If you are getting a wheel with the same widths all round then the same tyre profile all round ( positive side is you can rotate ur wheels and tyres ) A lot of Skyline owners get staggered sets nowadays with wider rims for the rear, better traction for rwd obviously :(

Well i was thinking about 245 on the rear and 225 on the front? Is that a good idea? Wider than stock obviously and should give me better steering and and traction in the dry... yes?What width rims would i need for that? Or is another choice preferable...?

Remember, my car has stock coils and suspension. So cant be TOO wide. but i dont know anything really, whats why im on here asking. :rolleyes:

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